Joao Pedro de Magalhaes pointed out the implications of recent work on cancer in mice:
It looks like cancer-resistant mice have a normal lifespan and age normally.
http://www.genesdev.org/cgi/reprint/gad.310304v1 (subscription required)
Here's a link to the story on BBC:
This is a very nice work by Manuel Serrano's group in Madrid as it shows that increasing cellular defences against damage, while influencing cancer, does not impact on aging. What it tells me is that aging is not merely a result from damage accumulation. It also raises questions on the link between cancer and aging--one which I've argued for in the past.
This is very interesting, to say the least, but I think it's a little premature to discount damage accumulation as the mechanism of aging - and the benefits of increasing cellular defences.
Dr Manuel Serrano used DNA technology to breed mice that had an extra copy of part of the tumour suppressor genes called Ink4a/ARF locus.
This locus controls the production of two proteins that together appear to stop most human cancer cells developing.
These 'supermice' were found to be extra resistant to things known to trigger cancer, called carcinogens, in normal mice.
Quite aside from all that, I think we should all be cheering the prospect of a genetic therapy that insulates people from developing most cancers!